The document discusses U.S. water rights policy and the energy-water nexus in the U.S. It outlines two systems of water law - prior appropriation in western states based on "first in time, first in right" and riparian rights in eastern states giving rights to landowners. The energy-water nexus and policy options are also discussed, including generating and sharing improved data, implementing efficient technologies, and incentivizing conservation. Las Vegas is presented as a case study for water management through recycling, efficiency measures, and incentives that have reduced residential water use from 650 to 75 gallons per day.